class Div implements ICalculate{
    private double result;
    public double calculate(double  m,double  n){
       if(0==n){
                   System.out.println("ERROR: / by zero!");
                   return 0.0:
      }
        result=m/n;
        System.out.println(m+"/"+n+"="+result);
        return result;
    }
}